1. Technical Field
The embodiments of the present disclosure relate to wireless communications and, more particularly, to the protection of multiple channels for full bandwidth wireless communications.
2. Description of Related Art
In the mobile communication area, one of the widely used protocols for use in communicating over a wireless local area network (WLAN) is the IEEE 802.11 protocol, including the various versions of the 802.11 protocol, such as 802.11a, 802.11b, 802.11g, 802.11n, and 802.11ac, etc. The IEEE 802.11a/b/g protocols generally transmit at a carrier frequency of 2.4 GHz or 5.0 GHz utilizing a single antenna, while 802.11n/802.11ac utilize multiple antennas implementing a technique commonly called Multiple-Input-Multiple-Output (MIMO).
The IEEE 802.11 protocol is established as a standard and utilized extensively in wireless communications. A common network implementation for a WLAN is a Basic Service Set (BSS), in which components of the BSS communicate with each other. The BSS may be a simple system, in which the BSS has a central coordinating device, such as an Access Point (AP), and one or more Stations (STA). In some instances, components of a BSS may form an ad-hoc system. A BSS may be a more complicated system as well, in which STAs may communicate with one another via peer-to-peer communication without utilizing an AP. In some instances, a device may communicate separately with its own subset of devices via a peer-to-peer link, such as a piconet.
The early IEEE 802.11 protocols specified and used a channel bandwidth of 20 MHz. However, as the numbers of wireless devices proliferate and demand for data transfers overburden the 2.4/5.0 GHz bands, new techniques are now being implemented to enhance the data transfer capability. The 802.11n protocol allows for two channels to be combined, so that an effective bandwidth of 40 MHz is used for the data transfer. A new protocol, IEEE 802.11ac further defines operations up to a bandwidth of 80 MHz and even up to 160 MHz. In cases of operating at multiple sub-channels (where each sub-channel has a bandwidth of 20 MHz), the 802.11 protocol defines a primary sub-channel. Some management frames, such as beacons, are transmitted using the primary sub-channel only. Moreover, despite the full bandwidth operation being established, using a sub-set of sub-channels to communicate is allowed, but the primary sub-channel is always included.
Although 802.11n and 802.11ac enhance the data phy (physical layer) rate by increasing the transmission bandwidth, new problems emerge when using more than 20 MHz of bandwidth (e.g. 40/80/160 MHz). For one example, despite the wider bandwidth operation that a BSS is capable of, some frames (such as beacons) are mandated to be transmitted using the primary 20 MHz bandwidth sub-channel. Also, sometimes the device may choose to use only a sub-set of 20 MHz bandwidth channels to transmit. If there is another BSS (Other BSS, noted as OBSS) operating at a 20 MHz sub-channel adjacent to one's own BSS's (MyBSS's) primary channel and within MyBSS's channel operation coverage, OBSS's communication can cause interference over MyBSS's communication.
A solution is to find a way to protect the channels needed for a wider or full bandwidth communication that uses multiple channels.